The application relates to a process for the preparation of aldobionamide.
U.S. Pat. No. 5,401,426 (counterpart of EP 569,869) discloses a process for the preparation of lactobionamide compositions in which lactobionolactone is reacted with the appropriate fatty amines in a lower alkyl alcohol solvent.
Published German Patent Application No. DE 1,155,771 discloses a process for the preparation of aldobionic acid alkylamides, in particular of maltobionic acid, lactobionic acid or cellobionic acid alkylamides, in which the corresponding acid lactones are reacted with alkylamines in a dimethylformamide solvent.
According to the prior art processes for the preparation of aldobionamide, aldobionolactone is always used as the starting compound. Therefore, in the prior art, aldobionolactone must be prepared first and isolated in a prior process step by removing water from the corresponding aldobionic acid. However, because of the applicational properties of aldobionamides, it would be advantageous to prepare aldobionamides directly from the aldobionic acids in a single-stage process.